Implement backend API and database services in Docker setup

- Added a new `api` service for the NestJS backend, including health checks and dependencies on PostgreSQL, Redis, and MinIO.
- Introduced PostgreSQL and Redis services with health checks and configurations for data persistence.
- Added MinIO for S3-compatible object storage and a one-shot service to initialize required buckets.
- Updated the Nginx configuration to proxy requests to the new backend API and MinIO storage.
- Enhanced the Dockerfile to support the new API environment variables and configurations.
- Updated the `package.json` and `package-lock.json` to include new dependencies for QR code generation and other utilities.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/Dockerfile.ffmpeg

@@ -0,0 +1,25 @@
+FROM node:20-alpine AS builder
+WORKDIR /app
+
+# Copy package files for the worker
+COPY package.json package-lock.json ./
+RUN npm ci --ignore-scripts
+
+COPY . .
+RUN npm run build
+RUN npm prune --production
+
+# ── Production image with FFmpeg ──────────────────────────────
+FROM node:20-alpine AS production
+WORKDIR /app
+
+# Install FFmpeg
+RUN apk add --no-cache ffmpeg
+
+COPY --from=builder /app/package.json ./package.json
+COPY --from=builder /app/package-lock.json ./package-lock.json
+COPY --from=builder /app/dist ./dist
+COPY --from=builder /app/node_modules ./node_modules
+
+# The FFmpeg worker runs as a standalone BullMQ consumer
+CMD ["node", "dist/ffmpeg-worker/worker.js"]